Hobbies And Interests
Things You'll Need
Instructions
Mounting Mirrors
Mark the end of the Sonotube for the screws to attach the mirror mounting cell assembly. Drill the holes, then mount the mirror to the cell and then screw the cell into the end of the Sonotube. Follow the mirror mounting instructions that come with your mounting cell closely so as not to break the mirror.
Measure the length of the focuser, add 3 inches for the radius of the Sonotube and then subtract this number from the focal length of the mirror. You&'ll find the focal length in the specifications of your mirror. The number you get will be the distance from the center of the mirror after it is mounted to the center of the secondary mirror.
Drill a 1 1/4-inch hole in the side of the Sonotube directly above where the center of the secondary mirror will be mounted. Set the focuser assembly directly over this hole and screw the mount into the Sonotube as indicated in the instructions.
Mount the secondary mirror on the spider mount according to instructions that come with it. Position the spider mount so the mirror is centered directly below the focuser assembly. Mark the legs and drill holes for the mounting screws. Attach the spider and mirror assembly with the screws.
Look down the focuser and adjust the legs till the secondary mirror reflects the image in the large primary mirror directly up the focuser hole. You should see an image of your own eye in the center of the secondary mirror if you have it lined up properly.
Screw the finder scope to the side of the Sonotube a quarter of the way around the tube from the focuser assembly.
Mounting Box
Cut two 6- by 6-inch and two 6- by 7-inch plywood squares and assemble into an open-ended box that is 6 inches on a side on the inside.
Glue and screw the box together. Glue thin felt on the inside of the box to help hold the tube in place.
Cut two 5-inch round disks out of 1/2-inch plywood and glue them to either side of the open-ended box.
Glue felt strips around the edges of each of these plywood disks or ears.
Insert the telescope tube in the box and adjust its position till it balances when you hold the bottom of the ears with your fingers.
Stage Base
Cut two 12-inch circles out of plywood.
Glue the two old phonograph records on top of the two plywood circles and drill a 1/2-inch hole in the center through the plywood disks.
Set one disk on top of the other and align the holes for the carriage bolt.
Drill a shallow 3/4-inch hole on the side of the 1/2-inch hole on the bottom disk to recess the carriage bolt.
Insert the carriage bolt from the bottom up and hand tighten the bolt till the stage resists rotating, but still turns smoothly.
The Pillar
Cut two 6 1/2-inch wide by 26-inch tall plywood rectangular sides and one 6 1/4-inch wide by 20-inch tall rectangle for the front side of the mounting pillar.
Glue and screw together a three-sided pillar. Place the short side in front and the open side in back. The two long sides will stick up above the front.
Mark a half circle below the center of the top edge of the long sides. Cut the arcs out to create two semicircular cradles on top of the long sides of the pillars. Lay strips of felt to the edge of the arc. Test fit the ears of the mounting box into the cradle to ensure it fits snugly without binding. You may have to trim the cradles a bit to ensure a good fit. When the fit is good, glue the felt strips into the cradle.
Set the mounting pillar on the two turntables and glue it in place. Screw the pillar to the rotating stage with short screws. Don&'t screw into the phonograph record. To further secure the pillar, fit strips of 1- by 1-inch wood around the base. Glue and screw the strips to the base and to the pillar.
Slide the telescope into the mounting box. Set the ears of the mounting box into the cradle on the pillar with the open end toward the short front side of the pillar. This allows the scope to swing up and point straight up with the bottom of the tube inside the pillar.
Setup
Collimate the optics of the telescope according to the instructions that come with the optics.
Test the scope by focusing on a stationary object in daylight. Leave it for 15 minutes and return to make sure the scope hasn&'t slipped up or down or rotated off target.
Tighten the rotating stage to increase resistance to rotation if the test reveals lateral motion of the resting tube.
Recheck the balance of the tube in the mounting box by lifting the mounting box with two fingers under the edge of the disk-shaped "ears" on the sides. Slide the telescope in and out of the box till it balances to stabilize the up and down motion in the cradle.
Add thicker padding in the cradle if the mounting box rotates too freely in the cradle. After you&'ve made the mounting box sit more securely, test as before to make sure it&'s stable when left unattended.